Modern aircraft typically include a variety of warning systems for alerting flight crew of potentially unsafe conditions that may arise during flight. For example, a ground proximity or terrain avoidance warning system may provide a warning to the flight crew that the aircraft flight trajectory may place the aircraft into undesirably close proximity to terrain or obstacles. The warning may be emitted as one or more audible or visual signals to the flight crew upon detection of the undesirable condition. The warning may include a visual warning comprising the flashing of a warning lamp on an instrument panel of the flight deck. The warning may progress into an audible “pull up” or “terrain, terrain” command to the flight crew which may be continuously repeated until the flight crew sufficiently alters the flight trajectory of the aircraft.
Other aircraft warning systems may include a stall warning system which may be comprised of sensors, instrumentation and/or an angle-of-attack vane mounted on the aircraft exterior to monitor the angle of attack of the aircraft wings. As the angle of attack approaches the stall angle, the warning system may emit an audible alarm such as a series of beeps and/or a visual alarm comprising the illumination of warning lamps on the instrument panel or at other locations on the flight deck. When stall is imminent, the stall warning system may cause the control column to shake continuously as an indication to the pilot to increase airspeed and/or to push forward on the control column in order to reduce the angle of attack and avoid stalling.
In the above-noted examples, the warning systems are designed to warn the flight crew of conditions that generally require immediate action. However, during the course of a flight, the flight crew may perform a variety of other flight interaction tasks that may not require immediate action but which are necessary to ensure a safe flight. For example, during long-distance flights, the flight crew may be required to make position reports to ground-based air traffic control at specific locations along the flight route. Such position reports may be transmitted using voice radio communications or by way of datalink communications. Similarly, the flight crew may be required to report to air traffic control prior to starting the initial descent from cruising altitude.
Certain physiological factors may have an effect on the ability of the flight crew to remain alert to perform such flight interaction tasks. For example, fatigue may affect the flight crew and may result from the lengthy periods of time during which the flight crew must remain alert during a long-distance flight. On transoceanic flights, the aircraft may cross several time zones which may affect the quality of sleep of the flight crew at their destination location and may result in fatigue in the flight crew during the return flight home. Such fatigue may result in missed flight interaction tasks such as a missed initial descent report to air traffic control.
As can be seen, there exists a potential need for a system and method for alerting a flight crew of the need to perform a task by increasing the level of stimulation that is provided to the flight crew. Further in this regard, there exists a potential need for a system and method for providing stimulation to the flight crew in advance of scheduled flight interaction tasks such that the flight crew may anticipate and prepare for such tasks. Additionally, where permitted by airline operations, there exists a potential need for a system and method that facilitates controlled resting of one of the flight crew during non-critical stages of a long-distance flight.